“Our study shines a flashlight on the issue of the rising role and potential impact of the pharmaceutical industry on breast cancer research and highlights important questions that need to be addressed through further research,” said Dr. Jeffrey Peppercorn, assistant professor of medicine in University of North Carolina (UNC) School of Medicine’s division of haematology and oncology.

“The significance of our study is not to say that the drug industry does anything wrong – they are excellent at developing new therapies, and there are many recent examples in breast cancer research. But if more and more research is funded by drug companies, then the limited amount of funding coming from other sources may need to be directed to address other questions,” Peppercorn said.

The researchers reviewed all breast cancer clinical trials published in ten English-language medical journals in the years 1993, 1998 and 2003. The industry studies were more likely to yield positive results; 84 percent of industry-supported studies showed positive results, compared with 54 percent of non-industry studies.

“It’s been seen again and again in various branches of clinical medicine that studies that involve pharmaceutical industry sponsorship are more likely to have positive outcomes,” Peppercorn said. “It’s not fair to say at this point that it’s necessarily related to biased interpretation of results.” For instance, another explanation could be that industry makes smarter or safer choices about what drugs are brought to trial.

However, as industry funding becomes an increasingly dominant source of research funding, clinical questions that are not directly related to drug development may be neglected, Peppercorn said.